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Mild Cu(OTf)₂-Mediated C-Glycosylation with Chelation-Assisted Picolinate as a Leaving Group.

ABSTRACT: C-Glycosylation reactions of glycosyl picolinates with allyltrimethylsilane or silyl enol ethers were developed. Picolinate as a chelation-assisted leaving group could be activated by Cu(OTf)₂ and avoided the use of harsh Lewis acids. The glycosylations were operated under mild neutral conditions and gave the corresponding C-glycosides in up to 95% yield with moderate to excellent stereoselectivities.

SUBMITTER: Ye W

PROVIDER: S-EPMC8138965 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Mild Cu(OTf)2-Mediated C-Glycosylation with Chelation-Assisted Picolinate as a Leaving Group.

Ye Wenjing W Stevens Christopher M CM Wen Peng P Simmons Christopher J CJ Tang Weiping W

The Journal of organic chemistry 20200805 24

C-Glycosylation reactions of glycosyl picolinates with allyltrimethylsilane or silyl enol ethers were developed. Picolinate as a chelation-assisted leaving group could be activated by Cu(OTf)2 and avoided the use of harsh Lewis acids. The glycosylations were operated under mild neutral conditions and gave the corresponding C-glycosides in up to 95% yield with moderate to excellent stereoselectivities. ...[more]

PMID: 32691596

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